Method for configuring an interface unit of a computer system

ABSTRACT

A method for configuring an interface unit of a computer system with a first processor and a second processor stored in the interface unit. A data link is set up between the first processor and the second processor. A peripheral of the computer system is configured to store input data in an input data channel and to read output data from an output data channel, and the second processor is configured to read the input data from the input data channel and to store output data in the output data channel. A sequence of processor commands for the second processor is created such that a number of subsequences is created.

This nonprovisional application claims priority under 35 U.S.C. § 119(a)to German Patent Application No. 10 2015 107 296.3, which was filed inGermany on May 11, 2015, German Patent Application No. 10 2015 107299.8, which was filed in Germany on May 11, 2015, German PatentApplication No. 10 2015 119 201.2, which was filed in Germany on Nov. 9,2015 and German Patent Application No. 10 2015 119 202.0, which wasfiled in Germany on Nov. 9, 2015, and all of which are hereinincorporated by reference.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to a method for configuring an interfaceunit of a computer system and a computer system.

Description of the Background Art

Many computer systems have interface units for data exchange between amain processor and peripheral devices. An interface unit of this kindcan be designed, for example, as a plug-in I/O card. Many interfaceunits are equipped with their own processors for preprocessing incomingand outgoing data, whereby some interface units make it possible toadapt the programming of the processor in the interface unit flexibly tothe requirements of the program executed by the main processor.

For example, the company Digi International Inc. provides an interfaceunit, freely programmable by the user, under the product name RabbitCoreRCM4100. Another known approach is to store a plurality of programfunctionalities for preprocessing incoming and outgoing datapersistently in the interface unit. The publication U.S. Pat. No.6,189,052 B2, for example, describes this type of approach.

If the computer system is provided to execute the program, beingexecuted by the main processor, in hard real-time, then the processesrunning on the computer system, in particular, also the processesexecuted by the processor stored in the interface unit, must becompleted with certainty within a predefined time period. For thisreason, the processor in the interface unit should function efficiently;i.e., the largest possible portion of the processor commands performedby it should be linked expediently to the programmed preprocessing ofincoming and outgoing data. Furthermore, the processor stored in theinterface unit should operate as deterministically as possible,therefore have low jitter, so that it is possible to estimate the timeneeded for executing processes sufficiently well.

SUMMARY OF THE INVENTION

It is therefore an object of the invention to provide a method forconfiguring an interface unit of a computer system, which assures arapid and low-jitter execution of the program code, stored in aprocessor or a plurality of processors of the interface unit, forpreprocessing data exchanged between a main processor and a peripheralof the computer system.

In an exemplary embodiment, a method for configuring an interface unitof a computer system is provided, whereby the computer system has afirst processor and a first data link between the first processor andthe interface unit and a second processor is or is made to be stored inthe interface unit. The interface unit has at least two data channels,whereby a first input data channel can be designed as a data channel forstoring the input data and a first output data channel as a data channelfor storing the output data. Furthermore, a peripheral environment ofthe computer system is configured such that the peripheral environmentcomprises a number of peripheral devices and the peripheral environmentis designed to store input data in the first input data channel by meansof a second data link or to read output data from the first output datachannel. The interface unit can be designed to provide a data link forreading the input data stored in the first input data channel by thesecond processor and to provide a data link for storing output data inthe first output data channel by the second processor. A computerprogram is stored in the computer system, and the first processor isprogrammed to execute the computer program and during the execution ofthe computer program to assign a value, which is defined by the inputdata stored in the first input data channel, to a variable of thecomputer program.

It is provided according to an embodiment of the invention that asequence of processor commands is created and loaded in the secondprocessor, after the loading of the sequence in the second processor,the execution of the computer program by the first processor and theexecution of the sequence by the second processor are started, andduring the execution of the sequence the value, defined by the datastored in the first input data channel, is written at a first memoryaddress. The sequence of processor commands is created such that anumber of subsequences of processor commands is created, whereby a firstsubsequence represents a routine for reading in and processing at leastthe data stored in the first input data channel and a second subsequencerepresents a routine for reading in and processing at least the datastored in a second input data channel or represents a routine forprocessing data generated by the first processor and for storing theprocessed data in the first output data channel, and the sequence iscreated by the merging of the subsequences.

A subsequence in an execution of the method of the invention can beunderstood to be a series of processor commands to be executed by thesecond processor, which in their entirety form a routine for routinginput data, i.e., a routine for reading the input data from an inputdata channel and for storing the read input data at a memory addressreadable by the first processor, or which in their entirety form aroutine for routing output data, i.e., a routine for reading the outputdata from a memory address writable by the first processor and forstoring the read output data in an output data channel. In a furtherembodiment of the method of the invention, a subsequence can beunderstood in addition to be information, which unambiguously defines aseries of processor commands executable by the second processor, wherebythe processor commands defined by the subsequence in their entirety ineach case form a routine for routing input data or output data. In theembodiment mentioned last, each subsequence is present first in the formof such information and before loading of the sequence in the secondprocessor is translated into a sequence of processor commands executableby the second processor. For example, in an embodiment of the invention,each subsequence can be present first in the form of source codeautomatically written in a high-level language by a processor of thecomputer system, whereby before the sequence is loaded in the secondprocessor each subsequence for the second processor is compiled.

Input data and output data can be routed in unchanged form by asequence. A sequence can also include processor commands, however, inorder to preprocess or process read-in data and to route the read-indata in preprocessed or processed form.

According to an embodiment of the invention, a sequence can beunderstood as a series of subsequences created by the merging ofsubsequences, regardless of whether the subsequences are present as aseries of processor commands executable by the second processor or inthe form of information defining a series of processor commands.

Input data can be understood to be data generated by a peripheralcomponent of the computer system and provided for processing by thecomputer program executed by the main processor. Examples of input dataare measured values of a sensor or an actual load integrated into anautomotive simulation. An input data channel can be an interface unitdata channel configured for storing input data by a peripheralcomponent. Output data can be understood to be data generated by thecomputer program and provided for reading by a peripheral component.Examples of output data are control commands for an actuator of anactual load integrated into an automotive simulation. An output datachannel can be an interface unit data channel configured for storingoutput data for reading by a peripheral component.

An advantage of the method of the invention is that the routine,executed by the second processor, for processing input data and outputdata is created in the first processor, which is also charged with theexecution of the computer program. In an embodiment of the method,different subroutines of the computer program, which exchange data withthe peripheral during the execution of the computer program data, ineach case create a particular subsequence corresponding to therequirements of the particular subroutine. The sequence loaded in thesecond processor is thereby always adapted to the individualrequirements of the computer program stored in the first processor. As aresult, there is no need to maintain a large number of functionalitiesfor preprocessing, processing, and routing data persistently to thesecond processor. During the execution of the computer program, thesecond processor executes the sequence successively, i.e., performs theprocessor commands in the sequence in the received order, and investslittle computing capacity, in particular, no computing capacity, in theexecution of unproductive, i.e., not immediately useful, processorcommands such as jump instructions and function calls. Furthermore,there is no need for processor-side optimization measures to acceleratethe execution of the program code stored in the second processor, forexample, by caching, as a result of which a deterministic execution ofthe sequence by the second processor is assured.

A further advantage of the invention is cost reduction compared withsolutions known from the prior art. Because the second processor mayexecute the sequence of processor commands only successively, asufficiently rapid execution of the sequence is also assured when atechnically simple, cost-effective processor is used in the interfaceunit.

Preferably the computer program includes at least one first I/O driverand a second I/O driver, whereby the first I/O driver creates the firstsubsequence and the second I/O driver creates the second subsequence. AnI/O driver in the context of the invention can be understood to be asubroutine of a computer program task, whereby the I/O driver contains asubroutine for the exchange of data between the task and the peripheral.

In an exemplary embodiment, a configuration phase of the computer systemis begun before the execution of the computer program is begun, wherebya software instance generates the sequence during the configurationphase, whereby the sequence is empty immediately after generation by thesoftware instance, therefore still does not contain any processorcommands and no information defining a processor command, and wherebythe first I/O driver writes the first subsequence in the sequence andthe second I/O driver writes the second subsequence in the sequence. Inthis embodiment, the software instance generates the sequence as anobject, which is configured to receive a number of subsequences.

In an embodiment, the sequence is automatically optimized by a softwareinstance before the sequence is loaded in the second processor.Optimization of the sequence can be understood in particular to be thepurging of the sequence of redundant processor commands, for example, byremoving redundant processor commands or by inserting a command forrunning a strobe. Because of the independent creation of the individualsubsequences, redundant processor commands cannot be ruled out in thestill not optimized sequence.

A strobe can be taken to mean that at least two processor commands foroutputting a datum, i.e., at least one first processor command and asecond processor command for writing a value in a memory address, arenot carried out immediately after the particular processor command iscalled up by the second processor, but the first value to be writtenaccording to the first processor command and the second value to bewritten according to the second processor command are initiallyarchived, and that in the execution of the strobe by the secondprocessor the first value and the second value are writtensimultaneously or immediately one after the other. A strobe thus bringsabout a synchronization of the output of data in a sequence.

The subsequences can be created such that the sequence has a minimizednumber of jump instructions, in particular, no jump instructions.Further, the subsequences can be created such that the sequence containsno function calls.

Further, the second processor is or is made to be configured preferablynot to use any caching during the execution of the sequence, so that thetime needed for executing the sequence results unambiguously from thenumber of the processor commands in the sequence and from the clockingof the second processor.

In an embodiment of the method, the interface unit has at least twosecond processors operating in parallel, whereby an individual sequenceis created for each second processor. A second processor in thisembodiment can be understood to be any processor which is stored in theinterface unit and which has the properties of the second processor andwhich is provided to execute a processor command sequence.

The interface unit can have an FPGA (field-programmable gate array), andthe second processors stored in the interface unit are or are made to beimplemented as soft-cores in the FPGA, in particular such that thesoft-cores are or are made to be implemented as flow control processors.

In an embodiment of the method, the computer program includes more thanone task, and each second processor is unambiguously assigned to a task,whereby the sequence loaded in a specific second processor contains onlysubsequences of I/O drivers of the task the specific processor isassigned to.

Furthermore, each task with at least one I/O driver can be assigned apriority, and the second processors are preferably assigned to the taskwith the highest priority.

In an embodiment, the execution of the sequence in a second processor isstarted by a trigger signal, whereby a second processor executes thesequence precisely once after a trigger signal is registered by thesecond processor. The trigger signal in this case is generated by an I/Odriver or at predefined times by a timer.

A computer system is also provided with a first processor and aninterface unit with a second processor which is stored in the interfaceunit and is configured to carry out a method for configuring theinterface unit by means of the first processor. The computer system canbe designed to execute a computer program by means of the firstprocessor in hard real-time, in particular whereby the computer systemis designed as a hardware-in-the-loop simulator or as a rapid controlprototyping system.

A hardware-in-the-loop simulator in connection with the invention can beunderstood to be in particular a computer system, which is configuredand provided to be connected to the data inputs and data outputs of anembedded system, for example, an electronic control unit or amechatronic component, and which is configured furthermore, inparticular, also with respect to the hardware installed in the computersystem, to simulate the real environment of the embedded system in hardreal-time.

A rapid control prototyping system in connection with the invention canbe understood to be in particular a portable computer system, which isconfigured and provided to be integrated into a network of electroniccontrol units, for example, in an automobile, to take over temporarilythe task of an electronic control unit in the network and to exchangedata with electronic control units in hard real-time, to read in datafrom sensors, and to control actuators.

Further scope of applicability of the present invention will becomeapparent from the detailed description given hereinafter. However, itshould be understood that the detailed description and specificexamples, while indicating preferred embodiments of the invention, aregiven by way of illustration only, since various changes, combinations,and modifications within the spirit and scope of the invention willbecome apparent to those skilled in the art from this detaileddescription.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more fully understood from thedetailed description given hereinbelow and the accompanying drawingswhich are given by way of illustration only, and thus, are not limitiveof the present invention, and wherein:

FIG. 1 shows a schematic view of a computer system designed to carry outthe method of the invention;

FIG. 2 shows a representation of process steps for creating a sequenceof processor commands; and

FIG. 3 shows a representation of the creation of multiple sequences bythe first processor and their distribution to several second processors.

DETAILED DESCRIPTION

The illustration in the figure shows a schematic diagram of a computersystem HIL, designed as a hardware-in-the-loop simulator, abbreviated asHIL. Computer system HIL has a first processor CN and an interface unitIO formed as a plug-in I/O card, and a serial first data link DL1 is setup between first processor CN and interface unit IO. Computer system HILis configured to execute a computer program for simulating anenvironment of an electronic control unit ECU, for example, anautomotive control unit, for testing the software of the control unitECU, in hard real-time by means of first processor CN.

An FPGA is installed in interface unit IO, and the interface unit haseight data channels, of which four are input data channels IN1, . . . ,IN4 and four are output data channels OUT1, . . . , OUT4. Five interfaceprocessors ION1, . . . , ION5, which are programmed as so-calledsoft-cores in the FPGA logic circuit, are stored in the FPGA as secondprocessors.

The term “interface processor” is used hereafter synonymously with theterm “second processor” according to the claims. The term “interfaceprocessor” is used exclusively for the purpose of the better readabilityof the following explanations and, taken in isolation, contains notechnical specifications, unless this is stated explicitly.

The implementation of a soft-core in a programmable logic circuit, forexample, an FPGA, is familiar to the skilled artisan from the prior art.The five interface processors ION1, . . . , ION5 are implementedidentically and designed as flow control processors (FCPs), i.e., theirdesign and their command set are optimized for routing, preprocessing,and processing input data and output data. Each individual interfaceprocessor ION1, . . . , ION5 has only one computing core and is designedand provided to execute a sequence of processor commands successively.In particular, the interface processors ION1, . . . , ION5 do not haveany devices for accelerating the execution of a command sequence, asmany processors have, for example, caching or parallelization by aplurality of computing cores. Tests have shown that it is possible toimplement eight FCPs, designed simply in this way, as soft-cores in anFPGA.

In a preferred embodiment, interface processors ION1, . . . , ION5 arenot stored persistently in the FPGA, but are stored as a compilation ina flash memory of computer system HIL and are programmed in aconfiguration phase of computer system HIL before the execution of thecomputer program is started in the logic circuit of the FPGA, wherebyinterface processors ION1, . . . , ION5 are stored as unprogrammedprocessors; i.e., no processor commands are initially stored ininterface processors ION1, . . . , ION5.

Interface unit IO is connected via a second data link DL2 to aperipheral environment PER. Peripheral environment PER contains threeperipheral components: an actual load THR, an electronic control unitECU, and an extension box XB. Second data link DL2 is set up as aplurality of cable connections, which are run between the peripheralcomponents THR, ECU, XB of peripheral environment PER and data channelsIN1, . . . , IN4, OUT1, . . . , OUT4 of interface unit IO. The actualload THR is, for example, a throttle valve of an automobile. Because thecomputer program is not capable of simulating a throttle valve, thethrottle valve is integrated in the simulation as a physical component.First processor CN generates a control signal for an actuator of actualload THR according to the specifications of the computer program, andthe control signal is transmitted via a data output OUT1 of interfaceunit IO to the actuator. A sensor of actual load THR is read via a datainput IN1 of interface unit IO and the read sensor signal is evaluatedby first processor CN based on the specifications of the computerprogram.

Electronic control unit ECU is a physical control unit, for example, anautomotive control unit, which is integrated into the simulation, inorder to test the software stored in electronic control unit ECU forcorrect functioning. To this end, first processor CN simulates in hardreal-time the environment of the electronic control unit, in particular,other electronic control units, sensors, actuators, and drivingmaneuvers of the simulated vehicle, and to this end exchanges data withelectronic control unit ECU. The electronic control unit is configuredto read in output data from two output data channels OUT2, OUT3 ofinterface unit IO generated by first processor CN, and it is configuredto store input data, generated by the electronic control unit ECU, in aninput data channel IN4, for evaluation by first processor CN, forexample, a control signal for a component simulated by first processorCN.

Extension box XB contains further computer components, assisting firstprocessor CN in the execution of the computer program, in the form ofplug-in printed circuit boards. Extension box XB is configured to readin output data from an output data channel OUT4 and to store input datain an input data channel IN2.

Interface processors ION1, . . . , ION5 are connected via a firstmultiplexer MUX1, programmed in the FPGA logic circuit and controlled bya first arbiter (not shown), to first data link DL1, and the firstarbiter is configured to assure access for first processor CN toprecisely one interface processor ION1, . . . , ION5 by means of thefirst multiplexer. Interface processors ION1, . . . , ION5 arefurthermore connected to data channels IN1, . . . , IN4, OUT1, . . . ,OUT4 via a demultiplexer MUX2 and a second multiplexer MUX3, and asecond arbiter (not shown) is configured to assure access for one ofinterface processors ION1, . . . , ION5 to one of data channels IN1, . .. , IN4, OUT1, . . . , OUT4 by means of control of demultiplexer MUX2and of second multiplexer MUX3.

A processor (not shown), which is configured to receive an input datumfrom a peripheral component THR, ECU, XB of peripheral environment PERand to make the input datum available to one of the interface processorsION1, . . . , ION4 for reading, is stored in each of the four input datachannels IN1, . . . , IN4. A processor (not shown), which is configuredto receive an output datum from one of the interface processors ION1, .. . , ION5 and to make it available to a peripheral component ofperipheral environment PER for reading, is stored in each of the fouroutput data channels OUT1, . . . , OUT4.

The illustration in FIG. 2 shows process steps for creating a sequenceof processor commands for an interface processor ION1 in a preferredembodiment of the method of the invention. A first task TSK1 of thecomputer program stored in first processor CN includes a first I/Odriver IOD1, a second I/O driver IOD2, and a third I/O driver IOD3. In afirst process step S1, each I/O driver IOD1, IOD2, IOD3 of first taskTSK1 creates a subsequence for execution by interface processor ION1.First I/O driver IOD1 creates a first subsequence SUB1, second I/Odriver IOD2 creates a second subsequence SUB2, and third I/O driver IOD3creates a third subsequence SUB3.

First subsequence SUB1, second subsequence SUB2, and third subsequenceSUB3 each represent a routine for routing input data, stored in an inputdata channel, for storing at a memory address, readable by firstprocessor CN, or for routing output data, generated by first processorCN, for storing in an output data channel. Subsequence SUB1, SUB2, SUB3contain no function calls.

First subsequence SUB1, second subsequence SUB2, and third subsequenceSUB3 are present after the running of the first process step in the formof a sequence of program commands formulated in a high-level language,for example, a sequence of C++ commands. Each subsequence SUB1, SUB2,SUB3 contains at least one program command for routing an input datum oran output datum, for example, a command from the family of memcpycommands, as defined in the C++ language. An example is the commandmemcpy32, whose syntax in simplest form is as follows:

memcpy32(add2, add1, n);

The command, beginning at memory address add1, reads in a number of ndata of 32-bit word length and writes the data at memory address add2.If the command is meant for routing an input datum, then add1 is amemory address in an input data channel, therefore a memory address,which is writable and readable by the processor stored in an input datachannel, and add2 is a memory address readable by first processor CN. Ifthe command is meant for routing an output datum, then add1 is a memoryaddress writable by first processor CN, and add2 is a memory address inan output data channel, therefore a memory address, which is writableand readably by the processor stored in an output data channel. Each I/Odriver IOD1, . . . , IOD3 creates the memcpy32 commands with relativememory addresses as values for add1 and add2 in relation to a memoryaddress defined as zero within the particular I/O driver IOD1, . . . ,IOD3.

Each subsequence SUB1, SUB2, SUB3 is automatically created based on therequirements of task TSK1, in which the particular I/O driver isintegrated, and based on user-defined configuration data and is adaptedin each case to the individual requirements of task TSK1. In anexemplary application, first I/O driver IOD1 is provided to read out acontrol signal for a pulse width modulation of an actuator signal at aninput data channel IN1, and a user can specify by means of aconfiguration software whether only the duty cycle of the actuatorsignal is to be modulated or whether the duty cycle and the frequency ofthe actuator signal are to be modulated. In the first case, first I/Odriver IOD1 writes only one memcpy32 command for routing a target valuefor the duty cycle in first subsequence SUB1. In the second case, firstI/O driver IOD1 writes two memcpy32 commands in first subsequence SUB1,one for routing a target value for the duty cycle and one for routing atarget value for the frequency. First I/O driver IOD1 can create asubsequence SUB1 such that it contains exclusively one or more memcpy32commands. Apart from a number of memcpy32 commands, first I/O driverIOD1 can optionally write other program commands for preprocessing orprocessing the input data in first subsequence SUB1.

Similarly, each subsequence SUB1, . . . , SUB3 includes at least anumber of memcpy32 commands, but optionally can have other programcommands for preprocessing or processing input data or output data, forexample, program commands to scale input data or output data or toprovide them with a constant component.

In a second process step S2, subsequences SUB1, SUB2, SUB3 are merged toform a sequence SEQ1. To this end, a software instance first creates asoftware object SEQO. Software object SEQO contains a header field Hwith information on first I/O driver IOD1, second I/O driver IOD2, andthird I/O driver IOD3, and software object SEQO is configured to receiveand store a number of subsequences SUB1, . . . , SUB3 formulated in ahigh-level language. The I/O drivers of first task TSK1 then write oneafter another their respective subsequences SUB1, . . . , SUB3 insoftware object SEQO; i.e., first I/O driver IOD1 first writes firstsubsequence SUB1 in software object SEQO, then second I/O driver IOD2writes second subsequence SUB2 in software object SEQO behind firstsubsequence SUB1, and then third I/O driver IOD3 writes thirdsubsequence SUB3 in software object SEQO behind second subsequence SUB2.Software object SEQO now includes header field H and a first sequenceSEQ1, assembled from first subsequence SUB1, second subsequence SUB2,and third subsequence SUB3.

In a third process step S3, sequence SEQ1 is preprocessed to be loadedin an interface processor ION1. In a first optimization, the relativememory addresses in memcpy32 commands are replaced by absolute memoryaddresses, whereby the information necessary for this is obtained fromheader field H, and first sequence SEQ1 is supplemented by a command forexecuting a strobe. After the first optimization has been completed,first sequence SEQ1 is translated into a sequence of processor commandsreadable and executable by an interface processor ION1. In a secondoptimization, redundant processor commands are removed from firstsequence SEQ1.

After third process step S3 is completed, first sequence SEQ1 is presentas a sequence of twelve processor commands COM1, . . . , COM12, wherebyfirst subsequence SUB1, second subsequence SUB2, and third subsequenceSUB3 are each contained as a continuous sequence of processor commands.Three successive processor commands COM1, . . . , COM3 depict thefunctionality of first subsequence SUB1, four successive processorcommands COM4, . . . , COM7 the functionality of second subsequenceSUB2, and four other successive processor commands COM8, . . . , COM11the functionality of third subsequence SUB3. A strobe command COM12closing first sequence SEQ1 brings about the synchronous output of thedata of first subsequence SUB1, second subsequence SUB2, and thirdsubsequence SUB3. The successive execution of first sequence SEQ1 by asecond processor ION1 therefore corresponds to a successive running offirst subsequence SUB1, second subsequence SUB2, and third subsequenceSUB3. First sequence SEQ1 does not include any function calls and jumpinstructions.

In a fourth process step S4, the optimized sequence SEQ1 is loaded in aninterface processor ION1 assigned to task TSK1.

The illustration in FIG. 3 shows the creation according to the inventionof a plurality of sequences SEQ1, . . . , SEQ5 and the distribution ofsequences SEQ1, . . . , SEQ5 to a plurality of interface processorsION1, . . . , ION5. The creation of each sequence SEQ1, . . . , SEQ5occurs in the same way as the creation of first sequence SEQ1, asdescribed in the description of FIG. 2. In the illustrated exemplaryembodiment, the computer program, stored in first processor CN, includesa first task TSK1 with a first I/O driver IOD1, a second I/O driverIOD2, and a third I/O driver IOD3, a second task TSK2 with a fourth I/Odriver IOD4 and a fifth I/O driver IOD5, and a third task TSK3 with asixth I/O driver IOD6, a seventh I/O driver IOD7, and an eighth I/Odriver IOD8. First task TSK1, second task TSK2, and third task TSK3 areeach assigned a priority defined by a parameter PRIO, whereby the valueof PRIO is a natural number and the value PRIO=1 indicates a task withthe lowest possible priority. A software instance during theconfiguration phase assigns at least one interface processor ION1, . . ., ION5 to each task TSK1, TSK2, TSK3, which has at least one I/O driverIOD1, . . . , IOD8. The number of the interface processors ION1, . . . ,ION5 stored in interface unit IO is accordingly an upper limit for thenumber of tasks TSK1, . . . , TSK3 in first processor CN, which taskscan be configured to exchange data with the peripheral environment PER,therefore to store output data in an output data channel OUT1, . . . ,OUT4 or to read in input data from an input data channel IN1, . . . ,IN4. The software instance is configured to prefer highly prioritizedtasks in the assignment of interface processors ION1, . . . , ION5,therefore to assign preferably still unassigned interface processorsION1, . . . , ION5 to a task with a high priority. After theconfiguration phase has been completed, each interface processor ION1, .. . , ION5 is unambiguously assigned to a task TSK1, . . . , TSK3.

First task TSK1 and second task TSK2 are each assigned the lowestpriority (PRIO=1), and for this reason, only one interface processorION1, . . . , ION5 is assigned to both of them. A first interfaceprocessor ION1 is assigned to first task TSK1. The I/O drivers of firsttask TSK1, therefore first I/O driver IOD1, second I/O driver IOD2, andthird I/O driver IOD3, together create a first sequence SEQ1; i.e.,first sequence SEQ1 contains the subsequences created by first I/Odriver IOD1, second I/O driver IOD2, and third I/O driver IOD3. A secondinterface processor ION2 is assigned to second task TSK2. The I/O driverof second task TSK2, therefore fourth I/O driver IOD4 and fifth I/Odriver IOD5, together create a second sequence SEQ2; i.e., secondsequence SEQ2 contains the subsequences created by fourth I/O driverIOD4 and fifth I/O driver IOD5.

Third task TSK3 is more highly prioritized than first task TSK1 andsecond task TSK2, for example, because the rapid processing of the inputdata read in by third task TSK3 is particularly important or becausethird task TSK3 processes large amounts of input data and for thisreason requires many computing resources in order to process the inputdata read in by third task TSK3 in hard real-time. The priority assignedto the third task is PRIO=5. Third task TSK3 for this reason is assignedthree interface processors ION3, ION4, ION5, so that the I/O drivers ofthird task TSK3, therefore sixth I/O driver IOD6, seventh I/O driverIOD7, and eighth I/O driver IOD8, each have available their owninterface processor ION1, . . . , ION5 for storing a sequence SEQ3, . .. , SEQ5, and an individual sequence SEQ3, . . . , SEQ5 is created foreach I/O driver of third task TSK3. Sixth I/O driver IOD6 creates asubsequence and writes the subsequence in a third sequence SEQ3. SeventhI/O driver creates a subsequence and writes the subsequence in a fourthsequence SEQ4. The eighth I/O driver creates a subsequence and writesthe subsequence in a fifth sequence SEQ5. Third sequence SEQ3, fourthsequence SEQ4, and fifth sequence SEQ5 each contain only a singlesubsequence.

The created sequences SEQ1, . . . , SEQ5, as described in thedescription of FIG. 2, are translated and optimized into a processorcommand sequence readable and executable for an interface processorION1, . . . , ION5, and the converted and optimized sequences SEQ1, . .. , SEQ5 are loaded into interface processors ION1, . . . , ION5. Firstinterface processor ION1 is assigned to first task TSK1; for thisreason, first sequence SEQ1 is loaded into first interface processorION1. Second interface processor ION2 is assigned to second task TSK2;for this reason, second sequence SEQ2 is loaded into second interfaceprocessor ION2. Third interface processor ION3, fourth interfaceprocessor ION4, and fifth interface processor ION5 are each assigned tothird task TSK3. Third sequence SEQ3 is loaded in third interfaceprocessor ION3, fourth sequence SEQ4 in fourth interface processor ION4,and fifth sequence SEQ5 in fifth interface processor ION5.

After the configuration phase is completed, the execution of thecomputer program by first processor CN and the execution of sequencesSEQ1, . . . , SEQ5 by interface processors ION1, . . . , ION5 arestarted. Sequences SEQ1, . . . , SEQ5 contain processor commands inorder to read input data from an input data channel IN1, . . . , IN4, toprocess them, and to write a result of the processing of the input dataat a memory address readable by first processor CN, and a task TSK1, . .. , TSK3 reads the value stored at memory address and assigns a value toa variable of the computer program based on the value stored at thememory address. Sequence SEQ1, . . . , SEQ5 contain furthermoreprocessor commands to read values from a memory address writable byfirst processor CN, to process the read value, and to store the resultsof the processing as output data in an output data channel OUT1, . . . ,OUT4. Each sequence SEQ1, . . . , SEQ5 is adapted individually to therequirements of the particular task TSK1, . . . , TSK3, and eachinterface processor ION1, . . . , ION5 successively processes thesequence SEQ1, . . . , SEQ5 stored in it. The parallel execution ofsequences SEQ1, . . . , SEQ5 in a plurality of interface processorsION1, . . . , ION5 rules out, moreover, that the execution of a sequenceSEQ1, . . . , SEQ5 is interrupted in favor of the execution of adifferent sequence SEQ1, . . . , SEQ5 of a more highly prioritized taskTSK1, . . . , TSK3. A rapid, i.e., time-optimized, and low-jitterexecution of sequences SEQ1, . . . , SEQ5 is assured in this way.

The invention being thus described, it will be obvious that the same maybe varied in many ways. Such variations are not to be regarded as adeparture from the spirit and scope of the invention, and all suchmodifications as would be obvious to one skilled in the art are to beincluded within the scope of the following claims.

What is claimed is:
 1. A method for configuring an interface unit of acomputer system, the method comprising: providing the computer systemwith a first processor and a first data link between the first processorand the interface unit and a second processor is or is made to be storedin the interface unit; providing the interface unit with at least twodata channels, wherein a first input data channel is designed as a datachannel for storing input data and a first output data channel isdesigned as a data channel for storing output data; configuring aperipheral environment of the computer system such that the peripheralenvironment comprises at least two peripheral devices and the peripheralenvironment is configured to store input data in the first input datachannel or to read output data from the first output data channel via asecond data link; configuring the interface unit to provide a data linkfor reading the input data stored in the first input data channel by thesecond processor and to provide a data link for storing output data inthe first output data channel by the second processor; storing acomputer program in the computer system; programming the first processorto execute the computer program and during the execution of the computerprogram, assigning a value, which is defined by the input data stored inthe first input data channel to a variable of the computer program;creating a sequence of processor commands and loading the sequence inthe second processor; starting, after the loading of the sequence in thesecond processor, the execution of the computer program by the firstprocessor and the execution of the sequence by the second processor;writing, during the execution of the sequence, a value defined by thedata stored in the first input data channel, at a first memory address;and creating a plurality of subsequences of processor commands, whereina first subsequence represents a routine for reading in and processingat least the data stored in the first input data channel, wherein asecond subsequence represents a routine for reading in and processing atleast the data stored in a second input data channel or represents aroutine for processing data generated by the first processor and forstoring the processed data in the first output data channel, and whereinthe sequence is created by merging the subsequences into a series ofsubsequences.
 2. The method according to claim 1, wherein the computerprogram includes at least one first I/O driver and a second I/O driver,wherein the first I/O driver creates the first subsequence and thesecond I/O driver creates the second subsequence.
 3. The methodaccording to claim 2, wherein a configuration phase is started beforethe execution of the computer program is begun, wherein a softwareinstance generates the sequence during the configuration phase, whereinthe sequence is empty immediately after generation by the softwareinstance, and wherein the first I/O driver writes the first subsequencein the sequence and the second I/O driver writes the second subsequencein the sequence.
 4. The method according to claim 1, wherein thesequence is optimized before the sequence is loaded in the secondprocessor, and wherein redundant commands are removed from the sequenceor redundant memory accesses are removed from the sequence or aprocessor command to run a strobe is added to the sequence.
 5. Themethod according to claim 1, wherein the sequence includes a minimizednumber of jump instructions or no jump instructions, or wherein thesequence includes no function calls.
 6. The method according to claim 1,wherein the second processor is or is made to be configured not to useany caching during the execution of the sequence.
 7. The methodaccording to claim 1, wherein the interface unit has at least two secondprocessors and an individual sequence is created for each secondprocessor.
 8. The method according to claim 7, wherein the interfaceunit has an FPGA and the second processors are or are made to beimplemented as soft-cores in the FPGA, and wherein the soft-cores are orare made to be implemented as flow control processors.
 9. The methodaccording to claim 7, wherein the computer program includes more thanone task and each second processor is unambiguously assigned to a task,wherein the sequence loaded in a specific second processor contains onlysubsequences of I/O drivers of the task the specific processor isassigned to.
 10. The method according to claim 9, wherein each task withat least one I/O driver is assigned a priority and the second processorsare assigned to the task with the highest priority.
 11. The methodaccording to claim 1, wherein the execution of the sequence in a secondprocessor is started by a trigger signal, and wherein the trigger signalis generated by an I/O driver or by a timer.
 12. A computer systemcomprising: a first processor; and an interface unit, wherein theinterface unit has at least two data channels, a first input datachannel being configured as a data channel for storing input data in theinput data channel by a peripheral environment and a first output datachannel being configured for storing output data for a peripheralenvironment, wherein the interface unit has a second processor, and theinterface unit is configured to provide a data link for reading theinput data stored in the first input data channel by the secondprocessor and to provide a data link for storing output data in thefirst output data channel by the second processor, wherein the computersystem has a first data link between the first processor and the secondprocessor, wherein the computer system is configured to start aconfiguration phase before the start of the execution of a computerprogram by the first processor during the configuration phase to createa sequence of processor commands and to load the sequence in the secondprocessor, wherein at least one first I/O driver and a second I/O driverare stored in the first processor, wherein the computer system isconfigured to create a plurality of subsequences during theconfiguration phase, wherein the first I/O driver is configured tocreate a first subsequence of processor commands during theconfiguration phase, wherein the first subsequence represents a routinefor reading in and processing at least the data stored in a first inputdata channel, wherein the second I/O driver is configured to create asecond subsequence of processor commands during the configuration phase,wherein the second subsequence represents a routine for reading in andprocessing at least the data stored in a second input data channel orrepresents a routine for processing data generated by the firstprocessor and for storing the processed data in the first data outputchannel, and wherein the computer system is configured to create thesequence by merging the first subsequence and the second subsequenceinto a series of subsequences.
 13. The computer system according toclaim 12, wherein the computer system executes the computer program viathe first processor in hard real-time, and wherein the computer systemis a hardware-in-the-loop simulator or as a rapid control prototypingsystem.
 14. The computer system according to claim 12, wherein thecomputer system creates the sequence with a minimized number of jumpinstructions or with no jump instructions.
 15. The computer systemaccording to claim 12, wherein the second processor is configured not touse any caching during the execution of the sequence.
 16. The computersystem according to claim 12, wherein the interface unit has at leasttwo second processors, and wherein the computer system creates anindividual sequence for each second processor and loads an individualsequence in each second processor.